Author Topic: SLS General Discussion Thread 2  (Read 424578 times)

Offline UltraViolet9

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Re: SLS General Discussion Thread 2
« Reply #1180 on: 12/30/2017 10:59 pm »
This certainly put a dent in the narrative that SLS was forced on NASA by congress. If what you said is true, then certain elements inside NASA is just as responsible for the current mass as congress, if not more so.

The relationship between congress, executive branch departments/agencies, and industry lobbies can be incestuous.  Wiki "Iron triangle (US politics)" or find a copy of Gordon Adams' old but essential The Iron Triangle: The Politics of Defense Contracting

In the case of the 2010 NASA Authorization Act, there were staffers involved on the relevant congressional committee who were recent employees of NASA and who were detailees from NASA and would be returning to the agency.  We obviously shouldn't expect critical thinking or independent oversight with that kind of revolving door.

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I guess this is NASA HSF's biggest problem, they're eternally optimistic about the budget.

And the costs of their programs.

Although that has been replaced recently with a refusal to generate cost estimates and provide budget assumptions, making program schedule, content, and/or risk entirely elastic.
« Last Edit: 12/30/2017 10:59 pm by UltraViolet9 »

Offline Bob Shaw

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Re: SLS General Discussion Thread 2
« Reply #1181 on: 12/30/2017 11:28 pm »
Yes, the smaller version of Direct would have used the existing 4 seg boosters from the Shuttle fleet.  It would use 3 RS-25's instead of the current 4, and could grow and stretch (later) to 4 or 5 engines, with a J2X upper stage.  The smaller version could have been fielded several years ago, and delivered 70 tons to orbit.  70 tons, with in space assembly could have done a lot, and be launched with current budget about 6 times a year.  Also, without the long delay that we had. 

SLS seems to have been an endless procession of u-turns, illogical assumptions and gold-plating. Add in the interminable development of Orion and there's a perfect example of the safest spacecraft and rocket ever - it rarely, if ever, leaves the ground.

I really can't comprehend why a side-mount STS cargo-carrier wasn't built, using almost off-the-shelf STS elements. Or why Shuttle-C wasn't pursued inj the first place. Sigh.

Offline spacenut

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Re: SLS General Discussion Thread 2
« Reply #1182 on: 12/30/2017 11:54 pm »
Looking backwards, Bob you are correct.  They could have had side-mount back in the 90's and got 50-60 tons to LEO, and still kept the shuttle fleet for human transportation.  At that point they could have beefed up the shuttle making the nose an escape pod to avoid a Challenger situation.  Maybe even escape during orbit re-entry also.  The side-mount could have delivered modules, cargo, and satellites, while the beefed up shuttle could deliver humans. 

Oh well, we got SLS whenever it gets built.  However by then SpaceX and BO will be delivering things with reusable first stages at least, and BFR/BFS will be coming along.  SLS will then be too big to operate efficiently. 

Offline Khadgars

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Re: SLS General Discussion Thread 2
« Reply #1183 on: 12/31/2017 06:07 pm »
Looking backwards, Bob you are correct.  They could have had side-mount back in the 90's and got 50-60 tons to LEO, and still kept the shuttle fleet for human transportation.  At that point they could have beefed up the shuttle making the nose an escape pod to avoid a Challenger situation.  Maybe even escape during orbit re-entry also.  The side-mount could have delivered modules, cargo, and satellites, while the beefed up shuttle could deliver humans. 

Oh well, we got SLS whenever it gets built.  However by then SpaceX and BO will be delivering things with reusable first stages at least, and BFR/BFS will be coming along.  SLS will then be too big to operate efficiently.

We don't need SpaceX in an SLS thread, there are 10,000 other threads for that.  Re-hashing out side-mount vs in-line is also long dead, I'm sure you could create a dedicated thread for it if you wish.

I do agree there are many decisions I think NASA would admit would do differently knowing how things panned out, however having said that they have created a remarkable launch vehicle and spacecraft. 

I've been listening to people claiming SLS was a paper rocket and would never make it past PDR for years, or that it would never launch.  At some point, opponents need to give it a rest and let things play out.  It may be we don't need SLS/Orion and it gets canceled, or equally as likely it ends up providing unique capabilities to cis-lunar space and Mars orbit that we need. 

Offline UltraViolet9

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Re: SLS General Discussion Thread 2
« Reply #1184 on: 12/31/2017 06:15 pm »
I really can't comprehend why a side-mount STS cargo-carrier wasn't built, using almost off-the-shelf STS elements. Or why Shuttle-C wasn't pursued inj the first place. Sigh.

They could have had side-mount back in the 90's and got 50-60 tons to LEO, and still kept the shuttle fleet for human transportation.

There were many less costly options for developing an STS-derived heavy lifter than SLS, and one of them could have gone into service much earlier.

But they all would have carried the costs of the STS workforce and infrastructure.  And as we're seeing in the outyears for SLS/Orion, that doesn't leave much budget for exploration hardware development, payloads, and missions.


Offline AncientU

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Re: SLS General Discussion Thread 2
« Reply #1185 on: 12/31/2017 07:51 pm »
...

I do agree there are many decisions I think NASA would admit would do differently knowing how things panned out, however having said that they have created a remarkable launch vehicle and spacecraft
...

1. 'Have created' is incorrect tense.
2. In what ways are either spacecraft (capsule) or rocket 'remarkable?'
« Last Edit: 12/31/2017 09:40 pm by AncientU »
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Offline ShawnGSE

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Re: SLS General Discussion Thread 2
« Reply #1186 on: 01/01/2018 02:36 am »
If this thing about 2023 is indeed valid, what would be driving this delay from 2019-20?

Job security for Shelby's Alabama-based workers. SLS is, after all, little more than a massive jobs program at this point.

Very little of the SLS is built in Alabama.  The majority of fab and assembly is in New Orleans at Michoud.  The 2023 thing is almost certainly bogus.  Flight hardware is well into production with full stage integration scheduled for next year.  2019/2020 is a realistic target at this point.

Offline spacenut

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Re: SLS General Discussion Thread 2
« Reply #1187 on: 01/01/2018 01:26 pm »
Aren't the engines built in Alabama, the planning and design team is in Alabama. 

Then there are the solids built in Utah.

It will be launched in Florida.

So you have two senators from each state involved in the SLS.   This keeps it running.  Shelby is just the head of the committee for space. 

If other components are made in other states.  Then those senators will along with the 6 above will continue to vote to fund SLS.  At least until a president and administrator says we can contract out launches cheaper and get more done, and convince them to stop funding SLS and start funding stuff that is actually used in space to be launched by private launch providers.

Oh, BO (Blue Origin) was also mentioned in my thread above as a private provider.  In a few years BO, SpaceX, and ULA with Vulcan/ACES or Centaur V can launch 40 tons each into space.  What can you do with a lot of 40 ton payloads?  Twice the throw weight used to build the ISS with 20 ton or less modules. 
« Last Edit: 01/01/2018 01:30 pm by spacenut »

Offline Khadgars

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Re: SLS General Discussion Thread 2
« Reply #1188 on: 01/01/2018 07:17 pm »
Aren't the engines built in Alabama, the planning and design team is in Alabama.
The RS-25 engines were built, and are being reengineered and tested, in Mississippi.  The ICPS was built in Alabama at the ULA plant in Decatur.  The RL10 was probably built in Florida, but I'm not certain.  The SLS core stage tank parts were made in Germany and welded together in Louisiana on a machine assembled by a Swedish company.  MSFC's primary involvement is in structural testing and avionics, I believe. 

Alabama, by the way, now has one senator from each party.

 - Ed Kyle

It was my understanding that the work for RS-25 is mainly conducted at two Aerojet Rocketdyne centers per the NSF article.

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The work is mainly conducted at two Aerojet Rocketdyne centers. The machining, welding, assembly and test of subassemblies takes place at its Canoga Park, California Strategic Fabrication Center. Turbopump assembly takes place at the West Palm Beach, Florida facility. Testing then takes place at Stennis.

https://www.nasaspaceflight.com/2016/01/nasa-defends-restart-rs-25-production/
« Last Edit: 01/01/2018 07:18 pm by Khadgars »

Online ncb1397

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Re: SLS General Discussion Thread 2
« Reply #1189 on: 01/01/2018 10:13 pm »
...

I do agree there are many decisions I think NASA would admit would do differently knowing how things panned out, however having said that they have created a remarkable launch vehicle and spacecraft
...

1. 'Have created' is incorrect tense.
2. In what ways are either spacecraft (capsule) or rocket 'remarkable?'

1.)Orion is the most capable spacecraft on the planet in any stage of production.
2.)SLS Block 1 is the most capable launch vehicle on the planet in any stage of production(in terms of payload volume, c3, and raw tonnage to any orbit).

BFR/BFS 2017 might change this but it is a paper rocket/spacecraft at this point, about as real as ITS 2016 was that was going to start flight testing in August 2018 according to Musk's timeline. We will see what it turns out being with all the work-arounds every spacecraft goes through during development and testing(see cross-fed FH, landing legs on Dragon, F9 reusable upper stage, etc.).
« Last Edit: 01/01/2018 10:24 pm by ncb1397 »

Offline Coastal Ron

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Re: SLS General Discussion Thread 2
« Reply #1190 on: 01/01/2018 11:38 pm »
Clongton mentioned in another thread that SLS is more or less DIRECT's Jupiter Heavy 244. Presuming similar motivations, How did SLS come to end up with such a large core stage?

It's important to remember the requirements, which came from the Senate members that created Senate Bill S. 3729. From that bill the requirements were defined as:

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(c) MINIMUM CAPABILITY REQUIREMENTS.—

(1) IN GENERAL.—The Space Launch System developed pursuant to subsection (b) shall be designed to have, at a minimum, the following:

(A) The initial capability of the core elements, without an upper stage, of lifting payloads weighing between 70 tons and 100 tons into low-Earth orbit in preparation for transit for missions beyond low-Earth orbit.

(B) The capability to carry an integrated upper Earth departure stage bringing the total lift capability of the Space Launch System to 130 tons or more.

(C) The capability to lift the multipurpose crew vehicle.

(D) The capability to serve as a backup system for supplying and supporting ISS cargo requirements or crew delivery requirements not otherwise met by available commercial or partner-supplied vehicles.

(2) FLEXIBILITY.—The Space Launch System shall be designed from inception as a fully-integrated vehicle capable of carrying a total payload of 130 tons or more into low-Earth orbit in preparation for transit for missions beyond low-Earth orbit. The Space Launch System shall, to the extent practicable, incorporate capabilities for evolutionary growth to carry heavier payloads. Developmental work and testing of the core elements and the upper stage should proceed in parallel subject to appro- priations. Priority should be placed on the core elements with the goal for operational capability for the core elements not later than December 31, 2016.

(3) TRANSITION NEEDS.—The Administrator shall ensure critical skills and capabilities are retained, modified, and devel- oped, as appropriate, in areas related to solid and liquid engines, large diameter fuel tanks, rocket propulsion, and other ground test capabilities for an effective transition to the follow- on Space Launch System.

(4) The capacity for efficient and timely evolution, including the incorporation of new technologies, competition of sub-ele- ments, and commercial operations.

Give those requirements, NASA created the SLS we are seeing today.
If we don't continuously lower the cost to access space, how are we ever going to afford to expand humanity out into space?

Offline notsorandom

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Re: SLS General Discussion Thread 2
« Reply #1191 on: 01/02/2018 12:55 pm »
Clongton mentioned in another thread that SLS is more or less DIRECT's Jupiter Heavy 244. Presuming similar motivations, How did SLS come to end up with such a large core stage?

To directly answer your question about large core:  there was a push to employ 5 seg SRBs (and 5 seg SRBs require a longer core stage than was used for STS).  One can assume that it was ATK pushing for the 5 seg, but I don't know for sure the drivers and decision-makers that insisted on 5 seg.
The 5 segment boosters did not require a longer core. Direct's Jupiter could have used them. The team published several baseball cards showing those configurations. The 5 segment boosters could even have been used on the Shuttle. The original proposals to add the extra segment date from when STS was still in full swing as a way to increase payload to the ISS and if I remember right enable abort to orbit right off the pad.

Offline spacenut

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Re: SLS General Discussion Thread 2
« Reply #1192 on: 01/02/2018 02:34 pm »
Wow, what a difference 10 years makes.  10 years ago, we were talking about Direct vs Constellation.  Which was the cheaper alternative and the quicker alternative.  Direct was of course.  We ended up getting SLS.  Now, 10 years later no rocket has flown, and it may be a few more years to flight at over $1 billion a pop. 

In that 10 years of bureaucratic development of SLS, Blue Origin has tested and landed a sub-orbital vehicle and developed the BE-3 engine, that in my opinion should be used on the upper stage of SLS, or a cluster of 2 or 3.  BO is also developing the BE-4 engine. 

Also in that 10 years SpaceX has developed the F9 into a reusable launch first stage vehicle, with FH about to come on line.  The have test fired the sub-scale Raptor and are on target to get Raptor developed.  They have finalized the basic design of BFR/BFS which will use Raptor. 

Meanwhile SLS plods along and still no rocket.  Really no new engines developed (liquid) that could actually improve SLS, such as liquid boosters, no RL-60, no AR-1, no RD-180 American made, J2-X didn't pan out, 5 seg solids were expensive to develop, no payloads of significance, and is going to wind up too expensive to operate more than once a year. 

All of the above makes SLS seem to us laymen as an expensive boondoggle now because of so called New Space bringing down costs and developing better reusable rockets.

So, what can be done to improve SLS and make it work at a lower cost?  Fly-back liquid boosters?, liquid boosters?  A good second stage?

Offline clongton

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Re: SLS General Discussion Thread 2
« Reply #1193 on: 01/02/2018 02:49 pm »
So, what can be done to improve SLS and make it work at a lower cost?  Fly-back liquid boosters?, liquid boosters?  A good second stage?

To make the SLS economical to operate and generally useful, NASA needs to do what it did with Transhab. It sold the rights to Bigelow Aerospace who turned it into something that is economical and useful. Get the government *and* the government contractors out of the SLS business entirely and maybe, just maybe, something could be done by a well positioned commercial company to make the vehicle useful and less expensive to operate.

In such a situation, the 1st thing I would recommend is to replace the SRB's with human rated reusable LRB's, similar to the Falcon 9 1st stage. That LRB, when equipped with a 2nd stage, should be capable of putting a fully fueled and outfitted Orion spacecraft into LEO. Reserve the HLV for cargo only and use the boosters as reusable Orion launchers.

Do that and we'd have something generally useful that could be operated at a reasonable cost.
« Last Edit: 01/02/2018 02:54 pm by clongton »
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Offline envy887

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Re: SLS General Discussion Thread 2
« Reply #1194 on: 01/02/2018 03:01 pm »
So, what can be done to improve SLS and make it work at a lower cost?  Fly-back liquid boosters?, liquid boosters?  A good second stage?

To make the SLS economical to operate and generally useful, NASA needs to do what it did with Transhab. It sold the rights to Bigelow Aerospace who turned it into something that is economical and useful. Get the government *and* the government contractors out of the SLS business entirely and maybe, just maybe, something could be done by a well positioned commercial company to make the vehicle useful and less expensive to operate.

In such a situation, the 1st thing I would recommend is to replace the SRB's with human rated reusable LRB's, similar to the Falcon 9 1st stage. That LRB, when equipped with a 2nd stage, should be capable of putting a fully fueled and outfitted Orion spacecraft into LEO.

Do that and we'd have something generally useful that could be operated at a reasonable cost.

Blue Origin is developing a LRB that fits that exact description, but I doubt Bezos wants anything to do with operating SLS. IMO NASA should twist Boeing's arm to buy and operate SLS since Boeing already builds the core stage. Boeing can buy NG LRBs from Blue, since their JV is already basically in bed with Blue for BE-4 anyway.

Offline spacenut

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Re: SLS General Discussion Thread 2
« Reply #1195 on: 01/02/2018 03:06 pm »
Is it too late to change directions?  They initially were trying to keep the existing shuttle work force, but that didn't work out.  Too long from shuttle decommissioning to SLS launching.  Also not enough SLS launches to justify a work force with only one launch a year. 

Is F9 capable of launching Orion with a single core in expendible mode?  Or with FH? in reusable mode? 

Can 4 F9's be strapped to an SLS core for boosters? 

My ideal rocket would be to make the RD-180 in America, build a 10m rocket with about 12 RD-180s around two RD-180s in the center and make it reusable with the two center ones used to land it.  Then use a cluster of 7 BE-3's for a second stage.  This would make for what I figure to be a 150 ton launcher.  Cheaper than SLS and partly reusable.  With the BE-3's the upper stage might be made reusable.  It would also be able to launch from the Cape.  It would be like a F9 on steroids. 

Offline Coastal Ron

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Re: SLS General Discussion Thread 2
« Reply #1196 on: 01/02/2018 03:27 pm »
Is it too late to change directions?

Yes, it's too late. The engineering phase for the initial version of the SLS is winding down and the SLS program is entering the production and test phase. I have no doubt what they are building will work and be safe, the only question is whether there is a need for it by the time it becomes operational.

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They initially were trying to keep the existing shuttle work force, but that didn't work out.  Too long from shuttle decommissioning to SLS launching.  Also not enough SLS launches to justify a work force with only one launch a year.

Politicians say the darnedest things, and not everything they say is true.

As to the future of the SLS, remember it takes an act of Congress to change it's current direction, and I don't expect Congress will want to increase the amount of money the program gets, so what you see is what you get.
If we don't continuously lower the cost to access space, how are we ever going to afford to expand humanity out into space?

Offline envy887

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Re: SLS General Discussion Thread 2
« Reply #1197 on: 01/02/2018 03:28 pm »
Anything can be done, if you convince enough people that it's worthwhile. The question is really is it worthwhile? And is it relevant to this thread? Orion on F9/FH and F9 boosters for SLS has been hashed out many times elsewhere. It's probably not worthwhile or relevant.

RP-1 main stage designs were considered and rejected for a variety of reasons before starting SLS in 2011, although I doubt fly-back designs or VTVL received any serious consideration. If VTVL designs are significantly successful, SLS will be wholly obsolete in short order. If they fail (either technically or economically), there is little reason to add them to SLS - the SRBs aren't driving much of the overall cost of the vehicle.

Offline RonM

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Re: SLS General Discussion Thread 2
« Reply #1198 on: 01/02/2018 04:04 pm »
So, what can be done to improve SLS and make it work at a lower cost?  Fly-back liquid boosters?, liquid boosters?  A good second stage?

To make the SLS economical to operate and generally useful, NASA needs to do what it did with Transhab. It sold the rights to Bigelow Aerospace who turned it into something that is economical and useful. Get the government *and* the government contractors out of the SLS business entirely and maybe, just maybe, something could be done by a well positioned commercial company to make the vehicle useful and less expensive to operate.

In such a situation, the 1st thing I would recommend is to replace the SRB's with human rated reusable LRB's, similar to the Falcon 9 1st stage. That LRB, when equipped with a 2nd stage, should be capable of putting a fully fueled and outfitted Orion spacecraft into LEO. Reserve the HLV for cargo only and use the boosters as reusable Orion launchers.

Do that and we'd have something generally useful that could be operated at a reasonable cost.

I agree, but the problem is a lack of payloads for SLS. If Orion is launched on a smaller rocket, the 1.5 architecture from Constellation, what is there to launch on SLS? Still need at least one flight per year to keep the program going.

Congress has supported SLS and Orion, but hasn't supported a program to keep them flying.

Online ncb1397

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Re: SLS General Discussion Thread 2
« Reply #1199 on: 01/02/2018 05:54 pm »
Wow, what a difference 10 years makes.  10 years ago, we were talking about Direct vs Constellation.  Which was the cheaper alternative and the quicker alternative.  Direct was of course.  We ended up getting SLS.  Now, 10 years later no rocket has flown, and it may be a few more years to flight at over $1 billion a pop. 

Yeah, Constellation was cancelled(shortly after a rocket did fly). This is what you can expect if you stop the pipeline, it takes a lot of time to get back going again building something different. You can see that with Commercial Crew replacing Ares-1/Orion. 8 years later and we are still waiting. These aren't shovel ready projects. Apollo would have gone the same way had it been canned in 67, or Shuttle had it been canned in 79.  But if all Constellation did was identify certain Lunar polar regolith is about 5% carbon monoxide and 5% water(with some other useful species for nitrogen) and kept the nuclear deterrent industrial base somewhat operational, it was at least somewhat useful.

Believe me, there will be more wasted money in space and dead ends before everything is said and done, which is just a small amount of what is wasted here on Earth. I mean, even stuff like wedding's/honey moons in space would probably be classified as waste even though it is economic activity and expands capabilities. Tourism at $7 trillion per year is probably where you want to go to find money you can save that is just conspicuous consumption that has little value. 10% of .5% of the federal budget is essentially nothing in the grand scheme of things. If it was really about the money, people would be probably just as upset that Planetary gets $2 billion per year but didn't launch anything this year.

edit: Actually, I was trying to find what the science mission directorate as a whole launched in 2017, and I couldn't find any dedicated launch. Was it all just co-manifested for ISS delivery and/or sub-orbital? I must be missing a launch here? Sigh, at least 2018 might be bonkers(hopefully, maybe...if a bunch of stuff doesn't blow up):

« Last Edit: 01/02/2018 06:53 pm by ncb1397 »

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